<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>红绿灯</title>
    <link rel="stylesheet" href="./css/红绿灯.css">

</head>

<body>
    <ul class="box">
        <li class="green"></li>
        <li class="yellow"></li>
        <li class="red"></li>
    </ul>
    <script src="./js/红绿灯.js"></script>
</body>

</html>